Can we inherit mental illnesses? Here is a question that some of us will one day ask, especially if some of our family members are suffering from mental disorders.De numerousresearches show that some mental disorders have a important genetics.
However, research has not yet been able to decipher all the questions about how this genetic load is acting or influencing.Science is moving slowly. We are gradually learning more about hereditary transmission of mental illnesses, although much remains to be done.
Disease, or rather health in general, and today understood as a product of the interaction between genetics and the environment. We also know thatwhat is hereditary is often not the disease, but the will to suffer it.
"Is it possible to inherit a mental illness? This is one of the most common questions asked by people with mental health problems."Share
What factors condition our health?
The onset of the disease will depend on many factors. This is so even in cases of inheritance of dominant characters. It is therefore possible to spend all one's life without the disease being manifested if there are no predisposing factors and triggers (the spark that ignites the wick carrying the genetic load).
We are therefore talking about probabilities. There is no certainty that the child of a patient with a mental disorderhas the same disease. On the other hand, we can predict that the probability of suffering will be greater. And if the father and the mother suffer from the same disease, the probability increases even more.
Now, what is the probability of inheriting some of the best-known mental illnesses?
Probability of inheriting mental illnesses: schizophrenia
Schizophrenia is a serious mental illness that affects certain brain functions such as thinking, perception, emotions and behavior. His symptoms belong to psychotic disorders, causing patients to lose touch with reality.
We estimate that 1% of the population suffers from schizophrenia. It is also estimated, based on different studies, that among 40% of the descendants of schizophrenic fathers and mothers will manifest the disease. Another 15% will have psychic abnormalities, but not the same illness.
Among bivitelline twins, the percentage of incidence is maintained. Among the univitellins, the concordance is 80%. It is therefore considered to be a recessive inheritance, with incomplete penetration of the gene or carrier genes.
Probability of inheriting bipolar disorder
Bipolar disorder is a serious illness because of the associated danger and disability.It is also known as manic-depressive illness or manic depression. People with bipolar disorder are characterized by unusual mood changes. This is one of the most feared mental illnesses.
People with bipolar disorder sometimes feel very happy and "lively". They are also much more energetic and active than usual. This is what we call a manic episode. People with bipolar disorder can feel very sad and "depressed". Have little energy and be much less active than usual. This is known as a depressive episode.
0.4% of the population has bipolar disorder. There is a risk that the disease will increase when parents suffer. Thea concordance is 95% among univitelline twins. It appears to be a dominant inheritance, with incomplete penetration of the gene.
What is the probability of inheriting oligophrenia?
Most deep oligophrenia (80%) are due to exogenous causes. In other words, accidents or diseases in the life of the womb or in infancy. They are therefore not hereditary.
80% of mild or moderate oligophrenias are related to heredity. These are children of people with low IQ. 80% of children are mentally retarded when their father and mother are oligophrenic. Only 40% have such a delay when only the father or the mother is oligophrenic.
A negative factor is that oligophrenes often unite with each other. So that the probability related to genetics is triggered. This is so because it is very difficult to find couples in which the distance of IQ is very large. The mode of transmission is recessive. Inheriting mental illnesses, such as oligophrenia, is possible, even if this results mostly from exogenous causes.
What about other mental illnesses such as neuroses?
Neuroses are abnormal experiential reactions, the result of circumstances. They are not linked to the genetic mass. The multitude of neuroses in the same family tree tends to be explained by "false inheritance". It is an illusion produced by "emotional contagion" in a family context that is conducive to it.
There is an inherited history in 70% of neuroses. The concordances in univitelline twins are 83%, but are only 23% in bivitellins. The hypothesis of an "emotional contagion" would remain in question.
There seems to be a constitutional background to the indisputable psychogenesis of neuroses. In other words,a predisposition to react neurotically to pathogenic experiences seems to exist.As we can see, it is possible to inherit mental illnesses. Some are more likely than others to be. Studies on twins and family history have shown thatMental illnesses have a variable genetic contribution.